Residential and commercial buildings often include a variety of alarms and alarm systems that may or may not be associated with a hazard detector. For example, local and/or state fire codes often require fire detectors, including but not limited to smoke detectors, in buildings that may be occupied. A variety of systems are available. A building may include a stand alone fire detector that provides an alarm directly from the stand alone unit upon detecting a predetermined fire condition. In another system, several fire detectors can be wired together such that when one detector provides an alarm, the other linked detectors also provide an alarm. In still another system, alarm generators separate from detectors can be wired to a central control panel, such that when one detector identifies a fire condition, the central control panel actuates some or all of the alarm generators to produce an alarm. Analogous devices and systems can also be used for detection of carbon monoxide and security breaches.
One problem of existing alarm systems is that hearing impaired persons may experience difficulty in recognizing the warning of a hazard condition. They might not hear an alarm or notice other people responding to an alarm and thus fail to become aware of an emergency situation. One attempt at resolving such a circumstance uses strobe lights or other warning lights to visually warn of a hazard condition. However, providing such lighting arrangements in every space within a building that may be occupied can be difficult and costly. Further, a hearing impaired person sleeping at home or being outside a home might not become aware of a hazard condition within the home.
Accordingly, an improvement in alarm systems is needed at least to alert hearing impaired persons of hazard conditions.